Current-converting device.



A'. R; BULLOCK.

CURRENT CONVERTING DEVICE. APPLlcATloN HLED Dfc.22, 1913. RENEwEDsEPLzo.1916. 1,2123,473.

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CURRENT CONVERTING DEVICE.

APPLICATION HLED DEC.22. 1913. nENEwED sEPT.2o. 1918.

1,223,473. Patend Apr. 24, 1917.'

3 SHEETS-SHEET 2.

,WaLn eses WWW `A. R. BULLOCK.

CURRENT CONVERTING DEVICE.

APPLICATION FILED DEC.22. 1913. RENEWED SEPZO. 1916; 1,223,473.

Patented Apr. 24,1917.

3 SHEETS-SHEET 3.

6, W vly ARTHUB n. BULLocK,

PATENT OFFICE.

OF CLEVELAND, OI-IIO.

CURRENT-CONVERTING DEVICE.

Application filed December 22, 1913, Serial No. 808,116.

T0 all wwm it may Gomera:

' Be it known that I, ARTHUR R. BULLOOK, a citizen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Current-ConvertingDevices, of which the following is a full, clear, and exact description.

This invention relates to a means for equalizing the fiow of currentfrom a plurality of terminals of a circuit in which a pulsating currentis flowing.

Generally speaking, the invention comprises the elements andcombinations thereof set forth in the accompanying claims.

Reference should be had to the accompanying drawings forming a part ofthis specification, in which Figure 1 is a top plan view of a currentconverting device. Fig. 2 is a section on the line A-B looking in thedirection of the arrow C. Fig. 3 is a section on the line A-B looking inthe direct'ion of the arrow A; Fig. L1 is a diagram of the electricalconnections; Fig. 5 is a diagram of the electrical connections where aplurality of brushes on the commutator are used.

In many instances it is necessary or desirable to split up a circuitcarrying a pulsating current, unidirectional or alternating, into aplurality of circuits connected in parallel and to cause each of thecircuits thus formed to carry an equal amount of current. This is not aneasy matter, particularly where all or part of these'parallel arrangedcircuits may be made and broken at times.

I have found, if such parallel arranged circuits each have a coil inseries and all these coils be arranged upon a single iron core so shapedthatv the magnetic circuit is closed, that the current, `flowing in eachcircuit is equal if the wire resistance of the circuit is equal.

As one example or instance of the application I would mention convertingdevices of such types as the vibratory rectifiers or rotating segmentrectifiers, which connect the sides of an A-C circuit alternately withthe sides of a D-C circuit, all produce from a single phase alternatingcurrent, a direct current which is highly pulsatng` in character.

Specfication of Letters Patent.

Patented Apr. 24, 1917.

Renewed September 20, 1916. Serial No. 121,312.

If such devices be provided with a plurality of positive terminals andnegative terminals, it is difiicult, if not impossible, to obtain anequal fiow of current from each of the terminals. It usually happensthat more current flows from one terminal than from another, due to theVariation in brush contact and vibrator button contact. This isdisadvantageous-in many instances, particularly in converting thedevices of the rotating' segment type which have heretofore beenmentioned for such devices, the current is usually collected by means ofrotating brushes, bearing on the segments, and it is necessary to use aplurality of brushes with such types of devices so as to increase thecurrent carrying capacity of the machine. It is quite essential that thecurrent cqually distribute itself between the brushes, otherwise asingle brush may be forced to carry a greater amount of current than it,

should, and produce a sparking or perhaps the more dangerous arcingbetween the brush and commutator.

1 have disclosed my invention in connection with a converting device ofthe rotating segment type. However, the invention itself is usable inother connections, and I do not limit myself to the use of the inventionin connection with the' machine of the disclosure.

In Fig. 1, a shaft 1 is supported in bearings 2 and 3, which may besuitably mounted upon. any standard or base. 'The shaft supports a'rotating body 4, which is provided with conducting portions or membersrepresent-ed at 5, G, 7 and 8 shown in Fig. 2. These conducting portionsare shown as segmented, merely because in commercial construction it ismore practical to make them in this fashion. However, as far as theelectrical principle underlying is concerned, each of these sections orportions might be a solid block of conducting material.

, Adjacent the body 4 and mounted upon the shaft 1, are collector rings9 and 10 which are insulated from the shaft and are insulated from eachother by an insulating body 11.

On the shaft 1 there is also supported a rotating body 12, this bodybeing provided with conducting portions 13, 14, 15 and 16.

The conducting portions 5 and 18 are electrically connected, as are theconducting portions 6, 7 and 8 with the conducting portions l-l, 15 and16 respectively. Also the conducting portions 5 and 7 are connectedtogether, and the conducting portions 6 and 8, and also the conductingportions 13 and 15 electrically connect, as is also the case with theconducting portions 14 and 16. The rings 9 and 10 are respectivelyconnected with the conducting segments 5, 7 and 6, 8.

A suitable support represented at 17 in Fig. 1 supports a ring 18 fromwhich extend brush supports, one of which is indicated at 19 in Fig. 1.These brush supports carry the usual brush holders, which bearrespectively upon rings 9 and 10 and upon the conducting portions uponthe body 4. As shown, four brushes are used which are so placed thatthey will simultaneously bear upon the same portions of each of theconducting portions upon the body 4.

A support 20 has mounted thereon rings 21 from which eXtend brushsupports 22, there being four of such brush supports, and these supportscarry the brush holders, there being four brushes, or four sets ofbrushes, as will be later explained, which bear upon the conductingportions of the body 12, as shown in Fig. 3.

The brushes 23 and 24 are electrically connected, and brushes 25 and 26are electrically connected with each other and also connected in serieswith the brushes 24 and 23. Brushes 27 and 28 are electrically connectedtogether, as well as brushes 29 and 30, and these last mentioned brushesare in turn connected with the brushes 27 and 28. This will clearly beseen by reference to Fig. 4.

The live portions or segments 13, 14:, 15, 16, are so related to thesegments 5, 6, 7 and 8 that the break in the circuit occurs betweensegments 13, 14, 15 and 16 and the brushes with which they coperate.That is brushes 23, 27, 25 and 29 break contact with their segments justbefore brushes 24,28, 26 and 30 break connection with their segments.

In series with the brushes 23 and 211 is a reactance coil which isgenerally represented at 31. In series with portions 25 and 26, there isalso a reactance coil 32, and these coils are in parallel with theconductor 33 which forms a part of the external D C circuit. These coils31, 32 are wound upon a common core 31a which is constructed to have aclosed magnetic circuit.

In series with brushes 27 and 28 is a reactance coil 311, and in serieswith brushes 29 and 30 is a reactance coil 35, these coils being joinedin parallel with a conductor 36 which forms a part of the external D Ccircuit. Coils 34-35 are wound upon a common core which is constructedto have a closed magnetic circuit.

The coils 31, 32, 31 and 35 are of equal number of turns and of the samesize of wire and when arranged as shown and described, the currentfiowing through the respective circuits in which the coils are located,will be equalized. If there is a tendency for a greater current to fiowthrough one circuit than the others, the equilibrium of the magneticfield is disturbed and reaction upon each of the lields set up by eachof the coils chokes the current flowing in the particular circuittending to carry excess current, and it finds a more ready path throughthe other cireuits, and so the oquality is preserrerl. Therefore each ofthe brushes with. which the circuits 31, 32, 34; and 35 are connectedwill lot through substantiall).Y equal amounts of current and willeliminatc the sparking iucident to unequal amounts of current beingcarried by the various brushes.

These reactances perform another function, at least those upon theopposite side of the D O line do, in that they prevent current flowingoutward from the battery during` the time that the voltage from theinachine is less than the Voltage of the battery.

In connection with a machine of this type, I use condensers which are soarranged and joined in the circuit that a condenser is always inparallel with the break upon both sides of the circuit, as the rotatablebodies which carry the conducting portions are caused to turn. Thesecondensers are arranged in two groups represented at 37 and 38, onegroup of condensers being connected in parallel with the line in whichthe reactance coil 32 is situated, and also connected with the line withwhich the reactance 35 is in series, and the intermediate points uponopposite sides of the condenser circuit are connected with the sides ofthe alternating current. The condenser group 38 is connected at onepoint with the circuit containing the reactance 31, and at the oppositepoint with the circuit containing the reactance 34, and the oppositeintermediate points upon the condenser circuit are also joined with thealternating current circuit. The manner in which these condensers areconnected is fully explained in a patent granted to me on December 2-1,1912, No. 1018,034, and their function in their present situation is thesame as that explained in that patent.

In many instances it is desirable to use a number of brushes bearing ona single segmented body, in place of using a single brush, this for thepurpose of increasing the current carrying capacity of the machine.

In Fig. 5, I have shown such an arrangenient, as is shown in Fig. 1,with the eXception that in place of the single brushes 211,

28, 26 and 30, and brushes 23, 27, 25 and 29, there are two brusheswhich are designated at 24a, 24h 28a, 28h, 26a, 26h, 80a, 80h, and 28a,

23m, 27a, 27611, 25a, 25, 29a, 29211.

For purposes of description, we may assume that the brushes 23a,23111,'21la and 24, and the brushes 25a, 25, 26EL and E20, areelectrically connected with the positive side of the D C circuit, whilebrushes 27a, 27211, 28a, 28, and brushes 29, 29, 30a, 301), areconnected with the negative side of the D C circuit. The groups ofsegments with which these 'brushes respectively coperatc, areelectrically connected with each other, and with the A G circuit, in thesame manner as is shown in Fig. 4.

The brush 24 and brush 28111 are connected with the reactance coil 2%;the brush 24a and brush 23a are connected with the reactance coil 24:0and so on throughout the brushes which are connected with the positiveside of the line. The brush 29a and brush 30a are connected with thereactance 29, while the brushes 30h and 292 are con-` nected with thereactance coil 29a, and so ou tln'oughout the brushes connected with thenegative side of the D C circuit.

lt will thus be seen that all of the brushes are individually connectedwith the D C circuit, through a reactance and these reactances are soproportioned that each will let through an equal amount of current.Therefore the total current flowing will be substantially equallyproportioned between the brushes, because of the readier path affordedfor the current.

lt will be apparent that more than two brushes may be used in each set,if desired.

As explained with respect to the machine indicated in the diagram ofFig. 4, I use condensers, the function of the condensers being the sameas that explained with respect to Fig. 4, and there is inserted a groupof condensers between each brush and coil connection upon the positiveside of the D C line, and a corresponding brush connected with thenegative side of the D C line, and this group of condensers will also beconnected with the alternating current circuit.

Explanation of one group of condensers, it is believed will sulfice forall. The group of condensers 37a' will be connected at diametricallyopposite points with the connection between the brushesal, 24h and thereactance coil 24= 1 and with the 4connection between the reactance coilQSC and the brushes 27111, 28h. The intermediate diagonally oppositepoints of the condenser group will be connected with the two sides ofthe A C Circuit.

1 do not limit my invention to use in connection with the hereindescribed machine,

as it will be apparent that its use may be of wider application.

Having described my invention, what I clam is:

1. The combination with a device for producine' a pulsating current,having a plurality of positive and negative terminals, and a reactancecoil connected in series with each terminal, a common core upon whichsaid coils are wound, the reactance coils for the positive terminalsbeing connected in parallel with each other, and the reactance coils forthe negative terminals being connected in parallel with each other.

2. The combination with an A O and D C circuit, of a device adapted toconnect the sides of o-ne of said circuits alternately with the sides ofthe other circuit, said device having a plurality of positive andnegative terminals, a reactance coil connected in series with each ofthe terminals, a common core upon which said coils are wound, thereactance coils for the positive terminals being connected with eachother in parallel, and the reactance coils for the negative terminalsbeing connected with each other in parallel.

The combination with an A C and D C eircuit, of a device adapted toconnect the sides of one of said circuits alternately with the sides ofthe other circuit, said device being provided with a plurality ofpositive and negative terminals, a reactance coil connected in serieswith each of the terminals, a common core upon which said coils arewound, the reactance coils for positive terminals being connected witheach other in parallel, and the reactance coils for negative terminalsbeing connected with each other in parallel, and a circuit containingcapacity adapted to be inserted between the sides of the C Circuit andeach pair of positive and neo'ative terminals of said device.

4;. The combination with a device for converting alternating current todirect current, the said device being provided with a plurality ofdirect current positive terminals, and a plurality of direct currentnegative terminals, and a reactance coil connected in series with eachof the positive and negative terminals, a common core upon which thecoils are wound, the reactance coils for the positive terminals beingconnected in parallel with each other, and the reactance coils for thenegative terminale being connected also in parallel with each other.

The combination with A C and D C circuits, of a device adapted toconvert the alternating current to the direct current, said device beingprovided with a plurality of direct current positive terminals, and aplurality of direct current negative terminals, a reactance coilconnected in series with each of the said terminals, a common iza coreupon which the cols are Wound7 the In testmony whel'eof7 I hereuntoaflix my l'eaetnce cols connected With the postve signature in thepresence of two Wtnesses. side of the D C Circuit, and the reactanceARTHUR R. BULLOCK. cols cennected With the negatve termnals, TNitnesses:

being connected in parallel With the nega- A. J. HUDSOJ,

tve Side of the D O crcut. L. I. PORTER.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington, D. 0.

